About OMICS Group...About OMICS Group Conferences OMICS Group International is a pioneer and leading...

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organizer, which publishes around 400 open access journals and

conducts over 300 Medical, Clinical, Engineering, Life Sciences,

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Shdai-140727

� Green ChemistryGreen ChemistryGreen ChemistryGreen Chemistry

� NPR toNPR toNPR toNPR to MDI,DDI,HDI:DPCMDI,DDI,HDI:DPCMDI,DDI,HDI:DPCMDI,DDI,HDI:DPC

� NIR to PNIR to PNIR to PNIR to P----Urea:DPCUrea:DPCUrea:DPCUrea:DPC

� NIR to PU through Cyclic CarbonateNIR to PU through Cyclic CarbonateNIR to PU through Cyclic CarbonateNIR to PU through Cyclic Carbonate

� Other CarbonateOther CarbonateOther CarbonateOther Carbonate Routes to PU and PARoutes to PU and PARoutes to PU and PARoutes to PU and PA

� SummarySummarySummarySummary

Prof. Prof. Prof. Prof. ShenghongShenghongShenghongShenghong A. DaiA. DaiA. DaiA. Dai

National ChungNational ChungNational ChungNational Chung----HsinHsinHsinHsin UniversityUniversityUniversityUniversity

Taichung, TaiwanTaichung, TaiwanTaichung, TaiwanTaichung, Taiwan

1

Green Processes to Diisocyanates and PU Elastomers

via Carbonate Raw Materials: New NPR and NIR Processes

Green ChemGreen ChemGreen ChemGreen Chem----2014 2014 2014 2014 PhiladelphiaPhiladelphiaPhiladelphiaPhiladelphia

Winterton: 12 Green Engineeing Principles

( Green Chem., 2001, 3 G73.)

1. Identify and quantify by-products. (副產物鑑定及量化副產物鑑定及量化副產物鑑定及量化副產物鑑定及量化)

2. Report conversions, selectivity's, and productivities. (明示程序之轉化率明示程序之轉化率明示程序之轉化率明示程序之轉化率/產率產率產率產率/選擇率選擇率選擇率選擇率)

3. Establish full mass-balance for the process. (建立完整質量平衡建立完整質量平衡建立完整質量平衡建立完整質量平衡)

4. Measure catalyst and solvent loses in air and aqueous effulent.

5. Investigate basic thermochemistry.

6. Anticipate heat and mass transfer limitations.

7. Consult a chemical or process engineer. (與化工人咨詢要點與化工人咨詢要點與化工人咨詢要點與化工人咨詢要點)

8. Consider the effect of overall process on choice of chemistry. (作完整化學選項之考量作完整化學選項之考量作完整化學選項之考量作完整化學選項之考量)

9. Help develop and apply sustainability measures.(發展永續發展之要項發展永續發展之要項發展永續發展之要項發展永續發展之要項)

10. Quantify and minimize the use of utilities.

11. Recognize where safety and waste minimization are incompatible. (安全及減廢之考量安全及減廢之考量安全及減廢之考量安全及減廢之考量)

12 Monitor, report, and minimize the laboratory waste emitted.

3 Shdai-140727


Shdai-131227

� Green chemistry Green chemistry Green chemistry Green chemistry is a wayis a wayis a wayis a way to minimize chemical threat to human to minimize chemical threat to human to minimize chemical threat to human to minimize chemical threat to human being and environment.being and environment.being and environment.being and environment.

� Anastas and Wnerer: ((((12 principles)12 principles)12 principles)12 principles) chemical reliability, safety, chemical reliability, safety, chemical reliability, safety, chemical reliability, safety, high selectivity,high selectivity,high selectivity,high selectivity, energy efficiency, reenergy efficiency, reenergy efficiency, reenergy efficiency, re----usability.usability.usability.usability.

� NPR / NIR- Our Green Research Goals:

---- Non-phosgene process of producing isocyanates

---- Minimize chlorineMinimize chlorineMinimize chlorineMinimize chlorine----containing reagents and productscontaining reagents and productscontaining reagents and productscontaining reagents and products---- Ambient synthesis conditionAmbient synthesis conditionAmbient synthesis conditionAmbient synthesis condition---- Use lowUse lowUse lowUse low----toxic chemicals toxic chemicals toxic chemicals toxic chemicals –––– avoid avoid avoid avoid isocyanatesisocyanatesisocyanatesisocyanates in PU makingin PU makingin PU makingin PU making---- Employ sustainable lowEmploy sustainable lowEmploy sustainable lowEmploy sustainable low----cost raw materialscost raw materialscost raw materialscost raw materials

• NPR: NonNPR: NonNPR: NonNPR: Non----phosgene Route (phosgene Route (phosgene Route (phosgene Route (非光氣製程非光氣製程非光氣製程非光氣製程---- IsocyanatesIsocyanatesIsocyanatesIsocyanates))))• NIR: NonNIR: NonNIR: NonNIR: Non----isocyanateisocyanateisocyanateisocyanate Route (Route (Route (Route (非異氰酸鹽製程非異氰酸鹽製程非異氰酸鹽製程非異氰酸鹽製程---- PU)PU)PU)PU)

Green Chemistry– NPR, NIR Processes

4


Phosgene Process-MDI from Benzene( Polyurethane Handbook by Huntsman)

Con. H2SO4/HNO3

Formaldehyde

Phosgene

5 Shdai-140727


Toxic chemicals

Phosgene Process- p-MDI from p-MDA

NH2H2NH2N

NH2

H2N x

+

N=C=O O=C=N x

+

COCl2

N=C=O

N=C=OO=C=N

(MDI) (p-MDI) x= 1 to 6

MDI Isomers Mp (C) Bp(C)

2,2’-MDI 46 140 / 0.5

2,4’-MDI 35 152 / 0.5

4,4’-MDI 41 161 / 0.5

60:40/2,4’:4,4’ 14

Ternary <0

MCB

Dist..

PhNCO &

low Boilers

4,4’-MDI

(>98.5%)

2,2-;2,4’-;4,4’-

MDI

Bottoms

Ref: H. Ulrich in “Chemistry and Technology of Isocyanates, John Wiley, p385 (1996)

PU

Rigid Foams

Crude MDA

P-MDA

6 Shdai-140727


The Problems Associated with Phosgene Process

� Safety problem: Phosgene is a highly toxic chemical with low Lethal threshold.

� Phosgene process generates large amount of HClg .

� HClg is a highly corrosive agent, and hence requires high-cost of maintenance.

� HClg needs to be managed into PVC or oxidized to recover as chlorine.

� MDI will contain hydrolyzable and non-hydrolyzable chlorides impurities.

� MDI process requires highly safety facilities to prevent accidents/fatality.

� Require large sum of initial cost for a large integration site and safety facilities.

7 Shdai-140727


Non-phosgene Routes to MDI

NNNCOOCN

H

O

RO

H

O

OR

N

H

O

OR

NN

H

O

O

H

O

OR'

NN

H

O

N

H

O

NR'

HHn

n

HO R' OH

H2N R' NH2

H2N R' NH2

HO R' OH

NH2

Carbonylation

Condensation

Thermolysis

Polyurea syntheses

Polyurethane syntheses

Amination

Trans-esterification

NH2H2N

CondensationCarbonylation

� Over 40 plus years of research but with no practical process in use

R= Me, Et, Ph

DPC (1)

(2)

(3)

8 Shdai-140727


(A) R-NO2 + 3 C=O R-N=C=O + 2 CO2

(B) R-NO2 + 3 CO + R’-OH R-NH-CO-OR’ + 2 CO2

(C) R-NH2 + CO + R’-OH + I/2 O2 R-NH-CO-OR’ + H2O

(D) R-NH2 + NH2-CO-NH2 + R’-OH R-NH-CO-OR’ + NH3

(E) R-NH2 + OR’-CO-OR’ R-NH-CO-OR’ + R’-OH

(F) R-NH2 + CO2 + R’X R-NH-CO-OR’ + HX

R-NH2 + Cl-CO-Cl R-N=C=O + 2 HCl

- R’-OH

Carbonylation ReagentsPhosgene still is the most efficient/cheap raw materials.

15 Shdai-140727


Olin

ARCO

Asahi

Bayer, BASF

Dow, Eni Chem,

Asahi

Monsanto

(current)

NPR to MDI – Prior Arts

ARCO : Three-Step Process from Nitrobenzene (1974)

NO2 NHCOOMe

NHCOOMe

NHCOOMeNHCOOMe

NHCOOMeNHCOOMeNCOOCN

+ CO + MeOH

2 + HCHOH+

(1) Reductive Cabonylation:

(2) Condensation:

(3) Thermolysis:

� Toxic catalyst and hart to recover [Step (1)]

� High temperature to crack carbamate [Step(3)] 9 Shdai-140727


Se

Asahi : Three Step Process from Aniline (1978)

1. Oxidative Carbonylation:

2. Condensation:

3. Decomposition:

NH2 + CO + EtOH + 1/2 O2NHCOOEt + H2O

(EPC)

NHCOOEt + CH2O- H2O

N-CH2-- NHCOOET

(N-benzyl compound)

N-CH2-- NHCOOET(EPC)

COOEt

COOEt

EtOCONH CH2-- NHCOOET

EtOCONH CH2-- NHCOOET

(MDU)

-2 EtOH O=C=N CH2-- N=C=O

H+

“Pd”

(MDI)

� Similar problems to ARCO’s; Being Scaled-up in pilot

240℃℃℃℃

10 Shdai-140727

NPR to MDI – Prior Arts


Lynodell’ DPC Route to MDI[ R. W. Mason, US Patent 6,781,010 (2004) ]

(1) MDA Condensation with Formic Acid:

(2) Carbonylation of Formamaide with DPC and Thermolysis:

(3) Trans-esterification of MDA with Phenyl Formate:

NH2NH

2

NHCHONHCHO+ HCOOH

NHCHONHCHOO

OPhNCOOCN

NHCOOPhNHCOOPh

NCONHCOOPh

+ PhO

+

(MDI)

MDI

HCOOPh + MDA NHCHONHCHO

180℃~200℃

180℃~200℃

+

HCOOPh

13 Shdai-140727


Lynodell’ DPC Process to MDI

[ R. W. Mason, US Patent 6,781,010 (2004) ]

� Advantages:Advantages:Advantages:Advantages:

- Themolysis temperature of biscarbamate into MDI seems milder (<200 ℃℃℃℃)

- The yields to MDA-formamaide and MDI are high.

- Phenyl formate, the by-product, could be re-used.

� Disadvantages:Disadvantages:Disadvantages:Disadvantages:

- MDI needs to be re-distilled to separate from solvent/by-product.

- Highly corrosive formic acid was used as the carbonylation agent.

14 Shdai-140727


Shdai-131227

Monsanto: CO2 Carbonylation-Dehydration Process

BASE PRESSURE CO2 DEHYD. AGENT % YIELD

NEt3 1 ATM POCl3 98%

NEt3 1 ATM PCl3 96%

NEt3 1 ATM SO3 99%

CyTEG 80 PSI (CF3CO)2O 91%

CyTEP 80 PSI SOCl2 70%

( 5mm) (10 mm) 25 ml

NPR to Aliphatic Diisocyanates

� Applicable only to aliphatic diamines

� Require strong tertiary amine to stabilize the initial carbamic acid

C8H17NH2 + 2 base1) CO2, CH3CN

2) 0 C; Dehydration

agent/ CH2Cl2

C8H17N=C=O

12


NPR to IPDI : Urea Route

� Applicable only to aliphatic diamine. (Bayer, Huls, BASF)

11 Shdai-140727


Franz M, USP 4,596,678(1986)

Shdai-131227Shdai-131227

Japan Asahi ( phenol system )

＋＋＋＋

Diphenyl carbonate

(DPC)

1,6-Hexanediamine

(HDA)Hexane-1,6-bis(phenyl carbamate)

2

Phenol

Thin film

Distillation

Column

(D=5cm 、、、、L=2m)

Excess

Phenol

Vacuum

Distillation

Thermolysis( 150~230℃℃℃℃ )

( 1.3~15KPa )

50℃℃℃℃Continuous

Process

Hexamethylene-1,6-diisocyanate

＋＋＋＋● Total operation time= 10 day

● Hexane-1,6-bis(phenyl carbamate) Yield= 99.5%

● DPC recycling rates= 99.9% ( 232℃℃℃℃、、、、15KPa、、、、119g/hr )

● Phenol recycling rates= 99.9% ( 230℃℃℃℃、、、、1atm、、、、200g/hr )

● HDI Yield= 95.3% ( 150℃℃℃℃、、、、1.5KPa、、、、140g/hr )

● HDI Purity= 99.8% ( L.C )

MW=116.21【【【【244g/116.21=2.1mol】】】】 MW=214.22【【【【1350g/214.22=6.3mol】】】】 MW=94.11【【【【987g/94.11=10.5mol】】】】

[24] M. Shinohata, N. Miyake, EP 2275405(2011) to Asahi

5L storage tank200g/hr

• Phenol as solvent and DPC as carbonylation agent

• Most similar to our approach for aliphatic iso

• Slow processing speed

NPR to Aliphatic Diisocyanates : Review of Prior Arts

(4) Carbonylation

(5) Thermolysis

32Shdai-140727


16

Principal Carbonylation Agents

>> >> >

> > > >

(Phosgene) (di-t-butylcarbonyl carbonate) (DPC, diphenyl carbonate)

(di-alkyl carbonate) (DMC, dimethyl carbonate) (urea) (carbon monoxide) (carbon dioxide)

Shdai-140727


NH2 CH2O

H2N NH2

O O

O

PhOOCHN NHCOOPhOCN NCO

Dai’s Group - 4,4’-MDI and P-urea Processes

Polyurea

(1) Carbonylation(2) Thermolysis

(3) Trans-esterification

MDA

MDA-DPCMDI

Aniline

(1) DPC carbonylation of MDA (2) Thermolysis to make MDI (3) NIR to Polyurea

17

Benzoic acid

Shdai-140727


O

OPh

NH2

NH2

NH2

O

OMeMeOO O

O

O

NCOOCN

NHCOOPhNHCOOPh

PhO

HCHO

PhOH

CO2 COMeOH

PU-Purea

PhOH

Potential Sources of DPG for NPR to MDI

(1) DPC/Benzoic

acid /cat.

(2) (3) Transesterification

18 Shdai-140727


NPR- Our Optimization of 4,4’-DP-MDC Synthesis

Fig 1. Effect of carboxylic acids

of different pKas on

4,4’-DP-MDC yields.

Fig 2. Effect of different benzoic acid

amounts on 4,4’-DP-MDC yields.

Fig 3. Effect of diphenyl carbonate

concentrations on

4,4’-DP-MDC yields.

Compositiona Biscarbamate

Yield (%)

Urea Yield(%)b

4,4’-MDA/DPC/Benzoic acid(1/6/0.2/0) 65 1.06

4,4’-MDA/DPC/Benzoic

acid/Pyridine(1/6/0.2/0.009)97 0.15

4,4’-MDA/DPC/Benzoic acid/TEDA(1/6/0.2/0.009) 99 0.15

aMolar ratio. At 40 C ~60 CbCalculated by 1H-NMR analysis.

Benzoic acid

identified5m% >

DPC/MDA = 6.0

19

• Catalyzed by

pyridine or TEDA.

Shdai-140727


NPR-Mechanism of Carbonylation:

Co-catalyzed by benzoic acid/tertiary amine

• Key active intermediate anhydride A in carbonylation of amine20

(carbamate)

Shdai-140727


NPR- MDA Carbonylation with DPC

( IR and 1H-NMR of the MDA-DPC; mp 194 ℃℃℃℃)

IR 1H-NMR

� MDAMDAMDAMDA----DPC/DPC/DPC/DPC/dodecanedodecanedodecanedodecane: No detection of : No detection of : No detection of : No detection of diphenyldiphenyldiphenyldiphenyl urea formationurea formationurea formationurea formation

4000 3500 3000 2500 2000 1500 1000 500

HH

NH

C

O

ONH

C

O

O

Tra

nsm

itta

nce

Wavenumber(cm-1)

1723cm-1

3335cm-1

3335cm-1

21 Shdai-140727


NPR-Thermolysis of MDI-DPC into MDI (a)

(Monitoring(Monitoring(Monitoring(Monitoring Thermolysis of MDA-DPC 200℃℃℃℃in Dodecane )

4000 3500 3000 2500 2000 1500 1000 500

Tra

nsm

itta

nce

W avenum ber(cm-1

)

3333cm-1

1721cm-1

2270cm-1

0hr

0.5hr

1.5hr

2 .5hr

HH

NH

C

O

ONH

C

O

OOCN NCO

HH

Pyrolysis

+OH

O

Cl

22


Shdai-140727

NPR- Thermolysis of MDA-DPC into MDI

� Isolated MMMMDI (76%) after fractionation

4000 3500 3000 2500 2000 1500 1000 500

Tra

nsm

itta

nce

Wavenumber(cm-1)

23 Shdai-140727


Summary of Lab-scale MDI Synthesis

� Carried out in dodecane (bp:216℃℃℃℃) at boiling temperature

� MDA-DPC conversion rate at 100%

� MDI crude yield >95%; Purified after distillation >76 %

� Recovered solvent and phenol >95%

� Little (CDI) by-product formation in the heating

� No chlorine content in the product

� The use of polar solvent resulted in complicated products.

24 Shdai-140727


NPR- Thermolysis of MDA-DPC into MDI (b)

H3C

O

N

H

O

O

Ph

H3C

O

N

H

NBu2

O

HNBu2 (1.05mmol)

solvent

Solvent DMSO DMF THF MeCN Dioxane DME CHCl3 MeOH Pyr TMS

結構式結構式結構式結構式

Bp(℃℃℃℃) 189 153 65 81 100 64 60 65 115 285

Relative

Polarity

(water=1)

0.444 0.404 0.207 0.46 0.164 - 0.259 0.762 0.3 0.41

Condition rt rt reflux rt reflux rt rt rt rt 70

Time 15min 15min 5h 1h 5h 24h 24h 24h 2.5h 2h

Yield(%) 96 74 92 79 65 92 90 74 85 89

( B. Thavonekham, Synthesis, 1997, 1189-1194 )

Trans-amination of Ph-carbamate in Different Solvents

25 Shdai-140727


硬鏈段鏈延長劑軟鏈段硬鏈段鏈延長劑軟鏈段

NIR-MDA-DPC and Diamines into Polyurea

NIR to P-urea

MDA-DPC Short Chain Extender Long Chain Diamine

Polyurea Elastomers26 Shdai-140727


Solvent Diamines Extender Hard Segment% Mol. Wt

DMSO Jeffamine-2000 1,6-HAD 57 54,400

DMSO Jeffamine-2000 PPG-230 61 71,000

DMSO Jeffamine-2000 1,8-diamino-3,6-dioxetane 58 131,000

TMS Jeffamine-2000 1,6-HAD 46 79,000a

(59,676)b

TMS Jeffamine-2000 H12-MDA 40 84,269a

(68,000)b

TMS Jeffamine-2000 IPDA 40 61,338a

(57,170)b

� Run at 60~100Run at 60~100Run at 60~100Run at 60~100℃℃℃℃ in in in in DMSODMSODMSODMSO as the solvent. (Hard to separate with as the solvent. (Hard to separate with as the solvent. (Hard to separate with as the solvent. (Hard to separate with PhOHPhOHPhOHPhOH ))))

� Run at 60~140Run at 60~140Run at 60~140Run at 60~140℃℃℃℃ in in in in TMSTMSTMSTMS with recovering of phenol/TMSwith recovering of phenol/TMSwith recovering of phenol/TMSwith recovering of phenol/TMS

a. Distilled phenol+ TMS b. just distill phenol after the reaction

NIR: Polyurea from MDA-DPC and Diamines

27 Shdai-140727


Run

No.

Polyurea Tda

(℃)

Tg

(℃)Yield

(%)

Tensile

Strength

(MPa)

Elongatio

n

(%)

ηinh TMS

Recovery

(%)

Phenol

Recovery

(%)

9 H12MDA-90-

DBa

290 -56.9 97 25.5 425.4 0.71 95 88

12 HDA-90-DB 287 -59.3 86 10.4 547.8 0.42 92 79

14 m-XDA-90-DB 280 -58.4 98 3.6 186.1 0.35 94 87

15 IPDA-90-DB 282 -57.3 100 16.9 1003.4 0.46 95 91

a 5% weight loss.B Distillation (140℃, 7×10-3 mmHg, 1h).

NIR- Polyurea Prepared in TMS

28 Shdai-140727


29 Shdai-140727


NIR-MDA-DPC Polyurea Prepared in TMS

“Non-Phosgene Route (NPR) to Aliphatic Diisocyanates”

WeiWeiWeiWei----HsingHsingHsingHsing Lin (Lin, WLin (Lin, WLin (Lin, WLin (Lin, W----S; Ph. D S; Ph. D S; Ph. D S; Ph. D Candidate; NCHU)Candidate; NCHU)Candidate; NCHU)Candidate; NCHU)

NPR to Aliphatic Diisocyanates

30 Shdai-140727

25℃℃℃℃ for 2hr

60℃℃℃℃ for 9hr

Benzoic

acid

Pyrolysis

Pyrolysis

Pyrolysis

DPC

DPC

EGDEE

EGDEE

DM-BPC

BM-BPC

ABA-DP-Biscarbmate

DDI

BDI

DDA

BDA

1-isocyanato-4-

(isocyanatomethyl)benzene; IBI

Pyrolysis

HM-BPC HDIHDA

Diphenyl ether

Our Overall 2-Step NPR Scheme: HDI, DDI, BDI, IBI (4) (5)

• Aliphatic ISO:

• Mixed ISO:

• Advantages: a. Reactivity DPC>> DMC; b. Lower temperature for isocyanate generation

(4) Carbonylation (5) Pyrolysis

33 Shdai-140727


25℃℃℃℃、、、、2hr

EGDEE; Recrystallization

75℃℃℃℃、、、、20min

65℃℃℃℃、、、、2hr(Vacuum)

Overnight

(RT)

(4) NPR First Step: Carbonylation of 1,12-dodecane Diamine

Filtration

34 Shdai-140727


NPR- Monitoring of Carbonylation by IR: C12 Diamine

25℃℃℃℃、、、、0hr

25℃℃℃℃、、、、10min

25℃℃℃℃、、、、1hr

25℃℃℃℃、、、、2hr

1777cm-1(C=O)

【【【【DPC】】】】

1698cm-1(C=O)

【【【【DMBPC】】】】

3280cm-1(N-H)

【【【【Stretching 】】】】

35 Shdai-140727


C-12 –biscarbamate preparation

Molar ratio DDA：：：：DPC＝＝＝＝ 1：：：：2.05

Weight ratio DDA：：：：DPC＝＝＝＝ 5 g：：：：10.96 g

Catalyst Catalyst-free

Nitrogen flux N2 =0.3L/min

Reaction solvent EGDEE＝＝＝＝ 48 g （（（（S.C=25% ））））

Reaction Temp. 25℃℃℃℃

Reaction time 2hr

DMBPC Yield 98％％％％

Urea yield Non

Melting point 121.5℃℃℃℃ ~ 122.4℃℃℃℃

NPR First Step: Carbonylation Data of 1,12-dodecane Diamine

36 Shdai-140727


NPR- NMR of 1,12-Dodecamethylene-Bis-phenyl carbamate

37 Shdai-140727


Temp Cel120.0100.080.060.040.020.0

DSC

mW

15.00

10.00

5.00

0.00

-5.00

-10.00

-15.00

-20.00

DD

SC

mW

/min

50.0

0.0

-50.0

-100.0

-150.0

-200.0

122.5Cel-12.74mW

Thermo-Data of 1,12-Dodecamethylene-Bisphenyl carbamate

Td(5%)= 181.6℃℃℃℃

Td(50%)= 228℃℃℃℃

Mp =123 ℃℃℃℃

38


NPR to 1,6-hexamethylene-bis(phenyl carbamate)

C-6-biscarbamate preparation

Molar ratio HDA：：：：DPC＝＝＝＝ 1：：：：2.05

Weight ratio HDA：：：：DPC＝＝＝＝ 215 g：：：：813 g



Agitation speed 200rpm

Reaction solvent EGDEE＝＝＝＝ 2500 ml

Reaction Temp. 25℃℃℃℃

Reaction time 2hr

HMBPC Yield 95％％％％

Urea yield Non

Melting point 127℃℃℃℃ ~ 128.2℃℃℃℃

39 Shdai-140727


Shdai-131227

[27] Luc Ubaghs, Isocyanate-free Synthesis of（（（（Functional））））Polyureas, Polyurethanes, and Urethane-

containing Copolymers , 2005, P.49

NPR- NMR of 1,6-Hexamethylene-Bis(phenyl carbamate)

40Shdai-140727


Biscarbamates DDI (C12) HDI (C6) BDI (C4)

Biscarbmate

Yield

DMBPC

98%

HMBPC

98%

BMBPC

89%

Melting point

(DSC)122.5 ℃℃℃℃ 126.6 ℃℃℃℃ 162℃℃℃℃

Td

(TGA; 5%)181.6 ℃℃℃℃ 147.4 ℃℃℃℃ 167.7 ℃℃℃℃

1-isocyanato-4-

(isocyanatomet

hyl)benzene

ABA-DP-

Biscarbamat

e

85%

175.8 ℃℃℃℃

167.7 ℃℃℃℃

Aliphatic Bis-carbamates Mixed

(4) Summary : Bis-Carbamate Preparations

• Excellent yield of biscarbamates could be prepared from C12, C6 and C4 diamine/+DPC.

• C4-biscarbamate crystal was contaminated ~ 6% of phenol that could not be separated.

• Preparation of ABA-biscarbamate is best done in two step. 41 Shdai-140727


Ice cool

Themal sensor

(inner)

Themal sensor

(outer)

Themal sensor

(distillation)

Heating belt

Fractionation

column

1,12-dodecamethylene-bis(phenyl carbamate)

Thermolysis

Dodecamethylene-1,12-diisocyanate

( bp = 168℃℃℃℃ at 3mmHg )

Benzoyl chloride as stabilizer

2

Diphenyl ether

( bp = 82℃℃℃℃ at 3mmHg or

250 ℃℃℃℃ at atm pressure )

Typical Set-up for Thermolysis of Biscarbamates

42 Shdai-140727


CG1020317

Weight DMBPC＝＝＝＝ 5 g

Catalyst Benzoyl chloride＝＝＝＝ 0.013 g

Nitrogen flux Non

Solvent Diphenyl ether＝＝＝＝ 45 g （（（（S.C=10% ））））

Pyrolysis

Initial NCO 180℃℃℃℃

Maximum NCO 254℃℃℃℃（（（（ HMBPC disappeared after 0.5hr at 240 ℃℃℃℃））））

Final All NCO peaks disappear

Reactor byproduct No yellow coking by-products

Flask

(Ice cool)

Initial product 240℃℃℃℃（（（（ Phenol appeared for 0hr at 240 ℃℃℃℃ ））））

Final product 254℃℃℃℃（（（（ Phenol appeared for 0.5hr at 240 ℃℃℃℃ ））））

1,12-diisocyanatododecane Yield 84％％％％

Phenol recycling rate 100％％％％

NPR- (5) Data on Isolation C-12 -Diisocyanate

43 Shdai-140727


minutes

Quantitative Analyses of C12-(NCO)2 by Quenching

C12-(NCO)2 + MeOH

4.4 （（（（Methanol））））

9.3 （（（（DDU））））

(1) Mobile phase= 55%Methanol + 45%H2O

(2) Wave length= 205nm

(3) Flow rate= 0.5ml/min

(4) Const flow rate

50mg DDU + 1ml Methanol

15mg DDU + 1ml Methanol

Yield＝＝＝＝84%

(by HPLC)

44 Shdai-140727


28

240℃℃℃℃、、、、0.5hr

Monitoring

DDI by IR

(1) Mobile phase= 55%Methanol+ 40%H2O

(2) Wave length= 205nm

(3) Flow rate= 0.5ml/min

Quantitative analyses of

DDU by HPLC

Experiment (3) – One-pot two-stage NPR process

Pyrolysis

Capped by 10X MEOH

(90 ℃℃℃℃ 1hr)

Separated by DDI and

Diphenyl Ether (Vacuum)

Reactor Flask (100%phenol)

SC = 18%

DMBPC → DDI

Pure DDI

(80%)

Pure Diphenyl Ether

(99%)

Reactor

Experiment (3) – One-pot two-stage NPR processDDI(S.C= 18%)

Phenol appeared

(One-pot)

Figure 12. DMBPC biscarbamates decrease (%) and DDI diisocyanates formation (%) in the pyrolysis in one-

pot two stage NPR process under 18% solid content in Diphenyl Ether at (a) 100℃℃℃℃, (b) 120℃℃℃℃, (c)

140℃℃℃℃, (d) 160℃℃℃℃, (e) 180℃℃℃℃, (f) 200℃℃℃℃, (g) 220℃℃℃℃ (phenol was collected in the flask), (h) 240℃℃℃℃, (i)

240℃℃℃℃-0.5 hr, (j) 240℃℃℃℃-1 hr.

Experiment (3) – One-pot two-stage NPR process

22

DMBPC → DDI CG1030203

Molar ratio DDA：：：：DPC＝＝＝＝ 1：：：：2.05

Weight ratio DDA：：：：DPC＝＝＝＝ 10 g：：：：21.9 g ( SC=25% )



Agitation speed 200rpm

Carbonylation solvent Diphenyl Ether ( DPE )＝＝＝＝ 96 g

Carbonylation Conditions 60℃℃℃℃、、、、2hr

DMBPC Yield ( HPLC ) 100％％％％

Pyrolysis solvent Diphenyl Ether ( DPE ) as pyrolysis solvent ( SC=18% )

Stabilizer

(Benzoyl chloride)None

Pyrolysis Conditions 240℃℃℃℃、、、、0.5hr ( 220℃℃℃℃→NCO, 220℃℃℃℃→Phenol )

Recycling rate Phenol =100％％％％、、、、Diphenyl Ether =99％％％％

Isocyanate Yield (HPLC) Pure DDI=80%、、、、Trimer=20%

Shdai-140727


Summary：：：：One-pot two-stage NPR processSummary：：：：One-pot two-stage NPR processSummary：：：：One-pot two-stage NPR processSummary：：：：One-pot two-stage NPR procesDDI HDI

Carbonylation solvent

(Reaction S.C%)

EGDEE(25%)

EGDEE(25%)

Molar ratioDDA : DPC

=1 : 2.05HDA : DPC

=1 : 2.05

Catalyst none none

Reaction condition 25℃℃℃℃、、、、2hr 25℃℃℃℃、、、、2hr

Biscarbmate Yield98%

(DMBPC)

98%(HMBPC)

Pyrolysis solvent

(Reaction S.C%)

DPE(10%)

DPE(2.5%)

DPE(10%)

Cracked time(carbamate disappeared)

240℃℃℃℃、、、、0.5hr

(254℃℃℃℃)

240℃℃℃℃、、、、2hr

(254℃℃℃℃)

240℃℃℃℃、、、、1.5hr

(254℃℃℃℃)

Stabilizer

(Benzoyl chloride)Exist

(1 / 145 )none Exist

(1 / 145 )

Isocyanate YieldDDI=84%

Trimer=16%

HDI=76%Trimer=12%

Biuret=8%

HDI=47%Trimer=14%

Biuret=4%

Allophanate=35%

DDI HDI

DPE(25%)

DPE(25%)

DDA : DPC=1 : 2.05

HDA : DPC=1 : 2.05

none none

60℃℃℃℃、、、、2hr 60℃℃℃℃、、、、2hr

100%(DMBPC)

100%(HMBPC)

DPE(18%)

DPE(16%)

240℃℃℃℃、、、、0.5hr

(260℃℃℃℃)

240℃℃℃℃、、、、1hr

(258℃℃℃℃)

noneBenzoyl chloride / HMBPC

= 1 / 145 (molar ratio)

DDI=80%

Trimer=20%

HDI=42%Trimer=34%Biuret=16%

Allophanate=3%

Two step (original process) One-pot two-stage NPR process

Summary：：：：One-pot two-stage NPR process

Non isocyanate / Phosgene Route (NIR/NPR)Chen, H.Y.; Pan, W. C.; Lin, C. H.; Huang, C.Y.; and Dai, S. A., Journal of Polymer Research, 19(2), 9754-9765,2012.

H2NR1

NH2

Diamine

Diphenylcarbonate

O O

O

Carbonylation

O NH

R1NH

O

O O

Diphenylcarbamate

OCNR1

NCO

Pyrolysis

Trans-esterification H2NR3

NH2

NH

NH

R1NH

NH

R3

O O

nPolyurea

(DPC) (6) Trans-esterification

(DPC)

(4)

(5)

47 Shdai-140727


NPR

NIR

O O

O+

Diphenyl Carbonate

H2NCH2

NH2m

Short Chain Diamine

+H2N

OO

ONH2

CH3 CH3

yx

CH3

z

Long Chain Diamine

One-pot

in TMS

90oC,3hrPhenol

pmPUaE

Hard Segment Soft Segment

48 Shdai-140727


NIR- Method 2: Two-step Process with Hard Segment Prepared First

O O

O+

Diphenyl Carbonate

H2NCH2

NH2m

Short Chain Diamine

Hard Segment

in TMS

90oC,1hr

Prepolymer

in TMS

90oC,3hr

hSPUaE

+H2N

OO

ONH2

CH3 CH3

yx

CH3

z

Long Chain Diamine

Soft SegmentPhenol

49 Shdai-140727


NIR- Method 3: Two-step Process with Soft Segment Prepared First

50 Shdai-140727


2000 1800 1600 1400

3 hr

1 hr

wavenumber(cm-1)

0 hr

1781

1736

1640

NIR- Monitoring by FT-IR in Method 3

51 Shdai-140727


Properties of NIR-PUaE

Methoda HSb

(%)

Yield

(%)

phenol

recycle

ratio

(%)

ηinh

Tdc

(℃℃℃℃)

Tg

(℃℃℃℃)

Tc

(℃℃℃℃)

Elongation

(%)

Tensile

strength

(MPa)

1

30

100 88 0.25 268 -62 / 174 3.84

2 97 82 0.49 262 -64 187 469 18

3 94 89 0.26 231 -65 170 92 3.28

1

40

94 78 0.29 250 -60 181 315 17.6

2 96 85 0.42 251 -60 192 160 15.2

3 89 84 0.28 243 -64 / 208 11.79a: Method of synthesis(1 :one pot ; 2: two steps-Hard first ; 3: two steps-Soft first)b: Hard segment ratioc: 5% weight lose temperature

52 Shdai-140727


NIR- Polyurea Analysis of GPC

0 5 10 15 20 25 30

0

5

Inte

nsity (

mV

)

Time (min.)

Method 1

Method 2

Method 3

Section 1

Section 2

Method

Area (%)

ηinhA1High Molecular Region

A2Median Molecular Region

A3Low Molecular Region

1 37% 45% 18% 0.25

2 44% 33% 23% 0.49

3 11% 83% 6% 0.26

Section 3

53 Shdai-140727


NIR- Method 4: Three-steps Process

+CH2 NH2H2N

m

Short Chain Extender

Hard Segment(1)

in TMS

90oC,1hr

Prepolymer

in TMS

90oC,1hr+

H2N ONH2

CH3CH3

n

Long Chain Diamine

Sof t Segment

Phenol

SPUaE (Segment Polyurea Elastomer)

DPC

O O

O

in TMSr.t.,1hr

+

CH2 NH2H2Nm

Short Chain Extender

Hard Segment(2)

54 Shdai-140727


NIR- Monitoring by FT-IR in Method 4

2000 1800 1600 1400

4hr

3hr

1hr

wavenumber(cm-1)

0hr

1781

1736

1640

55 Shdai-140727


Properties of NIR-Polyurea(Method 4)

short

chain

diamine

(1)

short

chain

diamine

(2)

long

chain

diamine

HSa

(%)

Yield

(%)

phenol

recycle

ratio

(%)

ηinh

Tdb

(℃℃℃℃)

Tg

(℃℃℃℃)

Elongation

(%)

Tensile

Strength

(MPa)

HDA IPDA D2000

30

94 96 0.56 264 -56 664 15.6

HDA IPDA ED2003 89 100 0.64 298 -60 1462 0.98

MDA IPDA D2000 68 65 0.23 283 -55 64 0.43

HDA IPDA D2000 40 83 44 0.62 284 -61 469 33.4

a: Hard Segment ratiob: 5% weight lose temperature

56


Shdai-140727

Analysis of AFM

3D-display

pmPUaE(DPC-D2000-IPDA)

roughness:1.09nm

hSPUaE(DPC-IPDA-D2000)

roughness:11.06nm

Method 1

Method 2

57 Shdai-140727


Analysis of AFM

sSPUaE(DPC-D2000-IPDA)

roughness:18.85nm

SPUaE(HDA-DPC-D2000-IPDA)

roughness:12.7nm

Method 3

Method 4

58


Shdai-140727

Shdai-131227

NIR -Conclusion

• Method 1：One step → Random → no phase separaHon

• Method 2：Hard segment first →gathered hard segment →

clear phase separation and better properties

• Method 3：SoJ segment first → scaKered hydrogen bond

→ small phase separaHon and poor properHes

• Method 4：：：：Three steps → high MW and phase separaUon

59


Shdai-131227

NIR Process with DPC

• Advantages of our PUaE:

� Raw materials (DPC and diamines) are inexpensive.

� Low chlorine in PUaE

� Can synthesize segmented PU elastomers

� Mechanical and thermal properties of PUaE are better

than traditional PU.

� In line with the principles of green chemistry

� Lower capital expenses for scaling-up

• Disadvantages:

- phenol/TMS recovery and recycle

60


Non-phosgene Route to PCs

59a

• In essence, our NPR process

to PU is comparable to that

BPA to PC of Asahi’process

both using DPC as the key

reagent. (taken from Principle

of Indstrial Organic Chemistry)

Shdai-140727


Non-Isocyanate Route to Polyurethane

via Cyclic Carbonates

Oleg L.Figovsky,Features of Reaction Amino-cyclocarbonate for Production of New Type Nonisocyanate Polyurethane

Coatings. Macromol.Symp, 2002,187(325~332)

Polyurethane

Cyclo bis(carbonate)s Diamine

+R

O

O O

O

O O

R'H2N NH2

O R O NH

R'NH

O

HO OH

O

n

O R O NH

R'NH

O

HO

OH O

n

OR

O NH

R'NH

O

OH OH

O

n

• Ring-opening reaction with no by-product generation

63 Shdai-140727


R

HN O

O

OO

O

R'NH2

b

R

HN O O

HN

R'

O

OH

O

R

HN O

O NH

R'

OH

O

a

R

HN

HN

R'

O

+OO

O

OH

(7) Products Found in CC-Amine Reactions

a

b

(ring-opening)

(trans-amination)

• Ring-opening of Glycerin cyclic carbonate

formed un-desirable urea by-products in

0.3~8%

•使用使用使用使用Model compound C (Model compound C (Model compound C (Model compound C (由由由由epoxyepoxyepoxyepoxy合成之合成之合成之合成之CC) CC) CC) CC) 並並並並無出現副產物的問題無出現副產物的問題無出現副產物的問題無出現副產物的問題

•所以在製備所以在製備所以在製備所以在製備NIPUNIPUNIPUNIPU時時時時,,,,盡量使用盡量使用盡量使用盡量使用Compound C typesCompound C typesCompound C typesCompound C types之之之之CCCCCCCC進行進行進行進行nonnonnonnon----isocyanateisocyanateisocyanateisocyanate為佳為佳為佳為佳....

65


Shdai-140727

• The system must be

strickly free from water

until used.

• The hydrolytically

unstable chemical bonds.

• The use of toxic/reactive

isocyanate.

Conventional PU (Iso/alc.) NIPU using CC/ amines

• Porous-free and moisture-

insensitive.

• Intermolecular hydrogen

bond endow NIPU with

good properties.

• Without using isocyanate.

(7) Comparison of PU and NIPU

66 Shdai-140727


(7) Cyclic Carbonate Formation from CO2 and Oxiranes

V. Calo, A. Nacci, A. Monopoli,Org. Lett. 2002,4,2561-2563

67 Shdai-140727


N. Kihara, T. Endo, J. Polym, Sci, 1993,31,2765-2773

OO

OO OO

O O

H2NNH2

Crosslinking PU

HDIAluminium triisopropoxide

(7) Crosslinked PU from HAD/CC from BPA-DGE

CO2BPA-DGE

(Epoxy)

68 Shdai-140727


Chen Kan-Nan’s Crosslinking Approach

69

J. Polym. Res., 2012, 19, 9900

Shdai-140727


70

(7) : Synthesis of M1 Prepolymer

1H-NMR

IR

OOO

O O

OOO

H2N

H2N

BCSDiglyme

@ 100°°°°C，，，，16hr

M1OO OHN

OH

O

NH2ON

H

OOH

H2N

n

GPC

70 Shdai-140727


Shdai-131227

PU(MBI-79XX-XX)

BI-7950(50%,75%,100%)

BI-7960(50%,75%,100%)

BI-7982(50%,75%,100%)

OO OHN

OH

O

NH2ON

H

OOH

H2N

n

Chain Extending by

Adding Blocked

Isocyanate

其中其中其中其中(50%,75%,100%)(50%,75%,100%)(50%,75%,100%)(50%,75%,100%)代表其末端胺的反應程度代表其末端胺的反應程度代表其末端胺的反應程度代表其末端胺的反應程度

(7): Chain Extending of M1 Prepolymer with Blocked Isocyanate

71

1111....由由由由EpoxyEpoxyEpoxyEpoxy Resin(BEResin(BEResin(BEResin(BE----188188188188))))合成出的合成出的合成出的合成出的AmineAmineAmineAmine----terminatedterminatedterminatedterminated prepolymerprepolymerprepolymerprepolymer 不會出現不會出現不會出現不會出現 ureaureaureaurea bybybyby----product,product,product,product, 但其但其但其但其分子量約在分子量約在分子量約在分子量約在1200120012001200左右左右左右左右,,,,而加入了商業化的而加入了商業化的而加入了商業化的而加入了商業化的BlockedBlockedBlockedBlocked isocyanateisocyanateisocyanateisocyanate作鏈長時作鏈長時作鏈長時作鏈長時,,,,其分子量呈現多區塊的分布其分子量呈現多區塊的分布其分子量呈現多區塊的分布其分子量呈現多區塊的分布,,,,無無無無法避免仍存在小區塊分子產生法避免仍存在小區塊分子產生法避免仍存在小區塊分子產生法避免仍存在小區塊分子產生....2222.... 由添加的由添加的由添加的由添加的blockedblockedblockedblocked isocyanateisocyanateisocyanateisocyanate之不同之不同之不同之不同,,,,交聯程度增加交聯程度增加交聯程度增加交聯程度增加,,,,可看見大分子區塊面積些微增加可看見大分子區塊面積些微增加可看見大分子區塊面積些微增加可看見大分子區塊面積些微增加,,,,第一區塊比第一區塊比第一區塊比第一區塊比例由例由例由例由4444%%%%~~~~10101010%%%%,,,,區塊由三個區塊由三個區塊由三個區塊由三個(MBI(MBI(MBI(MBI 7950795079507950))))變為四個變為四個變為四個變為四個(MBI(MBI(MBI(MBI----7982798279827982))))最佳最佳最佳最佳....3333....但主區塊的分子量成長有限但主區塊的分子量成長有限但主區塊的分子量成長有限但主區塊的分子量成長有限,,,,此部份仍未完全作最佳化此部份仍未完全作最佳化此部份仍未完全作最佳化此部份仍未完全作最佳化....


FTIR Monitoring of Preparing

BCS I+ 1,4-Bis(3-aminopropyl)-piperazine at eq ratio 1.25:1

in DMAc

產物命名產物命名產物命名產物命名: BCS type: BCS type: BCS type: BCS type----amineamineamineamine----BCSBCSBCSBCS過量比例過量比例過量比例過量比例----solventsolventsolventsolvent----溫度溫度溫度溫度----solid content solid content solid content solid content 若沒特別註明溫度為若沒特別註明溫度為若沒特別註明溫度為若沒特別註明溫度為100100100100°°°°CCCC solid solid solid solid cotentcotentcotentcotent 為為為為 lowlowlowlow72 Shdai-140727


Reaction of BCS II with1,4-Bis(3-aminopropyl)-piperazine

@100°C

1,4-Bis(3-aminopropyl)-piperazine

+

Mn MW PD

20130903 56,192 846,578 15.0657

• Tg = 78.1 C

• Td (5%) = 274 C

• Char Y = 1.64%

• E% = 7%

• TS = 20.84 Mpa

•%wt increase in water = 0.23%

(2wks)

73

In anisole

Shdai-140727


4000 3500 3000 2500 2000 1500 1000 500

cm-1

6hr

30hr

DMSO

Reaction of BCS II with1,4-Bis(3-aminopropyl)-piperazine

74

Cyclic carbonate

Carbamate

No sign of urea

In Anisole Solution

Shdai-140727


Shdai-13122775

Keys to High Molecular Weights PUs from Ring-

Opening of CC

• Selection of reactive diamines and bis-cyclic carbonates

• Suitable solvent to maintain efficient mixing

• High shear mixing of high viscosity products

• Mild reaction without by-product formation (< 100 C)

• Promoted by efficient catalyst: (Data obtained in different reaction time)


76

Summary

Successful NPR Developed Using DPC as Carbonylating agent:

MDA MDI

HMDA + DPC Biscarbamates HDI

DDA DDI

Successful Polyurea Elastomers Development via NIR

200-240℃

Biscarbamates

DPC Polyurea ElastomersHMDA/Jeffamine2000/IPDI

(One-pot three step)

PU Plastics Synthesized through NIR:

CC from Epoxy(BPA DGE)+Diamine PU (In Progress)

△

△△

Shdai-140727


77

Other NIR Process under Study(Dai Group)

(PC recycle and re-use as PU)

(GMA to ODMA to PU-acrylate/ DSM)

(Biscarbamate as blocked isocyanate)

Poly-(IPP-cyclic carboanate)

A.

B.

C.

D.

Shdai-140727


78

Acknowledgements

• 大東公司大東公司大東公司大東公司(GRECO)(GRECO)(GRECO)(GRECO) 新力美新力美新力美新力美(DSM)(DSM)(DSM)(DSM)

• NationalNationalNationalNational Science Science Science Science ConcilConcilConcilConcil of Taiwanof Taiwanof Taiwanof Taiwan

• Chen, S. Y Chen, S. Y Chen, S. Y Chen, S. Y (MDI) ; (MDI) ; (MDI) ; (MDI) ;

• Pan, Elisa Pan, Elisa Pan, Elisa Pan, Elisa ((((PolyureaPolyureaPolyureaPolyurea elastomerselastomerselastomerselastomers) ) ) )

• Lin,Lin,Lin,Lin, WWWW----SSSS (HDI,DDI)(HDI,DDI)(HDI,DDI)(HDI,DDI)

• Ku, K.T.Ku, K.T.Ku, K.T.Ku, K.T.(CC to PU)(CC to PU)(CC to PU)(CC to PU) Li, Li, Li, Li, 紫菁紫菁紫菁紫菁(CC to PU)(CC to PU)(CC to PU)(CC to PU)

Shdai-140727


79

Dai’s Group - 2012

Dai’s Group - 2013

(1)(2)

(3)

(4)

(3)

(1)(1)(1)(1) Chen, Chen, Chen, Chen, 陳學永陳學永陳學永陳學永

(2)(2)(2)(2) Ku, Ku, Ku, Ku, 顧冠增顧冠增顧冠增顧冠增

(3)(3)(3)(3) Pan, Pan, Pan, Pan, 潘玫蓁潘玫蓁潘玫蓁潘玫蓁

(4)(4)(4)(4) Li, Li, Li, Li, 李紫菁李紫菁李紫菁李紫菁

(5)(5)(5)(5) Lin, Lin, Lin, Lin, 林維興林維興林維興林維興

Shdai-140727


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